A collection of shielding calculators.

In the shielding technology a number of different tests are performed on the shield to confirm if shielding levels are as specified. The main tests in their order of application are:

• Seam sniffing by applying a low-frequency AM modulated current which flows on the outside of the shield. With an RF sniffer tool used inside the shield, all seams and entries are checked with the sniffer to check if the AM-modulated  signal can be detected inside. The quality of the seam closing is mainly determined by the type of gasket and the pressure on it.
  
• The sniffer test does not provide a dB shielding level and is a qualitative indication.
• The following three methods, H-field, E-field and Plane wave deliver the shielding level in dB.
  
• Low frequency Magnetic Field (H-Field) testing with magnetic loop antennas (10 kHz - 10 MHz ).
• Medium frequency (10 MHz - 1 GHz) Electric Field (E-field) testing with dipole structured antennas.
• High frequency (> 1 GHz) PW Field (Plane Wave) testing with yagi of gain-horn structured antennas, where the test distance >> wavelength and the field arrives as a plane wave.
• All shielding performances are depending on the skin-depth of the currents flowing through the metallic outside of the shield.